Coil retainer



F. c. cosEo. l COIL RETAINER.

APPLICATION FILED AFR. I1, I9I7- 1,414,7"753h Patented May 2, 1922.

WITNESSES: n

v A'TTORNEY.

' FREDE 'Be it known that I, F REDERIGK citizen. of the United States,`residing at Columbus, in thecountyof' Franklin and i State of Ohio, have invented certain new and y UNITED vSTATES PATENT OFFICE.

RICE c. cosEo, oEcoLUIIBua oIIIo, AssIGNoE To THE JEFFREY MANUFAC- TUEING coivIrANY, or COLUMBUS, oHIo, VA Coupon-Arron or oHIo.

coII. RETAINER.

nai/Ime.

iippiicaupnieu Aprn 17,

To all whom it may concern:

C. CosEo, a

useful Improvementsin Coil Retainers, of which the following isa specification, reference being had therein yto the accompanying y drawing.

The present invention relates vto certain new yand useful improvementsy in resilient coil retainers adapted to secure' `the field coils upon the pole pieces'ofelectric motors.

Theobject is to provide retaining devices firmly, hold a -coil of'aV relatively widely ex` tended base at its outer end, snugly against vpurpose are `fully set forth in the following specification and illustrated in the accompanying drawings of which- Y Fig. 1 is a transverse'section through the field frame of a four pole electric railway motor equipped with the devices of my invention. y

Fig. 2 is a plan view of one of the poles of such a motor showin the relation of the field coil and coil retainer thereto.

Fig. 3 is a section along the line 3--3` of Fio. 2. i

Fig. 4 is a section along the line 4-4 of Fi 2. Y i

lgiiike numerals refer to similar parts in the several figures.

For purposes of illustration I have shown, in Fig. 1 of lthe drawings, a section taken along the transverse central `plane of an electric motor, -of well known construction, adapted to railway service. The field frame of this motor comprises a magnetic yoke 1 upon which is formed Vfour field poles 2. At one side of the field oke 1 is formed a journal bearing 3 by which the motor is supported upon the axle 4 of the locomotive. At 5 on the side of the yoke- 1 opposite to the axle 4 the field frame is adaptedto engage with an abutment '6, attached to the frame of the locomotive, to prevent rotation of the motor about the axle 4. Attached to the Specification of Letters Patent. l Patented May 2 1922*.

1917. Serial N0.`1`62,726.

vfield poles by the attachment bolts 7 are .theA customary laminated pole shoes 8' having coils.' The coils 10 are connected into the circuits of the motor in such manner that the electric current will flow through the conductorV 11 of the coils in a direction to energize the field poles to produce the desired rotation of the armature 13. As these con-v nections form no part in the present invention vthey have been omitted from the vdrawings Afor the sake of simplicity, and are no t thought to require further description at this time.

Surrounding thepoleshoes 8 of each of the field poles is a non magnetic casting 14 which forms the abutment member of my improved coil retainer. At each side of the pole shoe 8 the abutment member 14 bears upon the outer surface ofthe projecting pole Vtips 9. Laterally extending flangesv 15 are formed at each side of the abutment member against which abut a plurality of outwardly extending compression springs 16. The outer ends of the springs 16 contact with a non magnetic retaining plate 17 which bears upon the inner surface of the field coils 10 to press it outwardly into Contact with the field frame 1. The pressure of the spring16 upon the retaining plate 17 is sufficient to prevent A movement of the coil relative to the field frame and the resiliency of the springs per- -mits the expansion and contraction of the coil without injury to the insulation'.

I am aware of the fact that it has been heretofore proposed to hold the coil in position by resilient retainers. Generally the device proposedv for this have been arranged between the curved frame metal and the coil; and the retainers have been placed in such way that the base or outer end of the coil was held at a distance from the frame. In the cases where the retainer was placed between the pole and the coil, use was made of elastic plates extending integrally from side to side of the core. i

I apply the elastic action at each of numerous points by devices which permit the retainer to yconform more delicately and closely to the positions of the different parts of the coil. I employ a plurality of small springs distributed between the two loose plates lll and 17. These extend around the core and apply pressure uniformly and in such way as to hold the wide base of the coil uniformly against the outer frame metal, avoiding losses of the magnetic lines and keeping the parts constantly in efficient relationship.

One ol: the serious di'tliculties incident to the use oi retaining devices of this class has been the reducing or the space between the pole tps and the frame metal which should be occupied by coil metal as completely as possible. In earlier devices either a space relatively deep (on the radii of the armature) at the inner or pole end has been lost, or a space at the outer or frame end of the core. iilien the parts are constructed and arranged as I. have shown there is, practically, ne loss ot space at all. The core metal is radially short, the plane at tlie inner extremity of the coil is in, or nearly in, the tangent plane at the bottoni oi" the curved surface of the pole, and the coil is extended outward to have its base end immediately adjacent the frame metal. The abutment device at l5 is nearly in the transverse or tangent plane of the pole tip 9, although its holder plate at 14 `is in the same transverse or tangent planes with the pressure plate 17. That is to say, I reach the utmost economizing possible of available space for the mounting of the resilient retainers.

In a coil retainer of the class described, the combination With a dynamo electric machine comprisingy a eld frame having inwardly projecting` poles with laterally projecting pole tips and field coils upon the poles, of pairs of non magnetic pole-encircling members interposed between said pole tips and said coils, and a plurality of independent and separately removable springs arranged to force said members apart thereby exerting outward pressure upon said coils.

In testimony whereof I affix my signature in presence of two witnesses.

FREDERICK C. COSEO. Vitnesses:

HARRY C. DEAN, DUDLEY T. FISHER. 

